Control for jarring mechanism in foundry machines



CONTROL FOR JARRING MECHANISM IN FOUNDRY MACHINES L. C- YOUNG Dec. 2,1952 3 Sheets-Sheet 1 Filed July 19, 1949 [III-5&0! l0 7 e 4 57 zINVENTOR. '0

L. C. YOUNG Dec. 2, 1952 CONTROL FOR JARRING MECHANISM IN FOUNDRYMACHINES Filed July 19, 1949 3 Sheets-Sheet 2 INVENTOR.

D- 1952 c. vduue ,619 5 CONTRQL. FOR JARRING MECHANISM IN FOUNDRYMACHINES Filed July 19, 1949 3 Sheets-Sheet 3 Patented Dec. 2, 1952CONTROL FOR J ARRING MECHANISM IN FOUNDRY MACHINES Lester C. Young,Cleveland, Ohio, assignor to Spo, Inc., a corporation of OhioApplication July 19, 1949, Serial No. 105,553

3 Claims.

My invention relates to molding machines and more particularly to joltmolding machines adapted to aid in compacting the molding sand or othermaterial.

In jolt molding machines, the jolt table is raised by a fluid pressurelifting means which comprises a piston element and a cylinder elementadapted to be extended relative to each other and defining an extensiblefluid pressure chamber. For the raising movement of the jolt table,fluid under pressure is introduced into the xtensible fluid pressurechamber to raise the jolt table relative to an anvil upon which the jolttable rests in its lowermost position. In operation, the jolt table israised a predetermined distance above the anvil, and then the fluid isexhausted from the fluid lifting chamber, which permits the jolt tableto fall by gravity and strike the anvil for producing a vjoltingoperation to aid in compacting the molding sand or other material in themolding flask or other container. In prior constructions, exhaust fromthe extensible chamber is eifected by providing an exhaust line which isnormally covered by the piston. As the piston and cylinder move relativeto one another, the exhaust line is opened and the fluid pressure isreduced. The jolt tabl then falls against the anvil. The prior devicesare designed for a particular upward stroke under a selected load, and adetermined severity of jolt impact under the selected load. Theseconditions cannot be varied after the machine is constructed, andconsequently, if a lightweight mold is carried, it will be shaken todestruction.

An object of this invention is to provide a jolt machine which may beadjusted to accommodate various sizes of loads.

Another object of this invention is to provide a controllable aircushion for a jolt machine.

Another object of this invention is to provide an adjustable thrust fora jolt machine before releasing the power for a return stroke.

Other objects and a fuller understanding of my invention may be had byreferring to the following description and claims, taken in conjunctionwith the accompanying drawings, in which:

Figure l is a transverse crosssectional view of a jolt molding machinebase unit employing the features of this invention, the unit being inthe lower rest position;

Figure 2 is the same sectional view as Figure 1, with the power chamberextended and the table raised into an elevated position;

Figure 3 is a transverse cross-sectional view of a modified form of ajolt machine base unit employing the features of. this invention, withthe power chamber extended and the table in a raised position;

Figure 4 is a broken away sectional view taken at a angle with respectto Figure 3, illustrating the air intake .lines into the extensiblechamber of th embodiment illustrated in Figure 3;

Figure 5 is the same sectional view as Figure 3, with the table in thelower rest position;

Figure 6 is the same view as Figure 4 in the lower rest position;

Figure '7 is a type of foundry equipment machine into which the baseunits of Figure 1 or 3 may b incorporated, the machine being of theroll-over type; and I Figure 8 is a stationary floor type of foundrymachine into which either of the base units of Figure 1 or 3 may bebuilt.

With reference to the Figure 1 of the drawing, my jolt machine comprisesgeneraly a base II), a jolt table 24, a fluid pressure lifting mechanismcomprising a piston I8 and a cylinder 29 interposed between the base Itand the jolt table 24, and outer tubular shell II projecting upwardlyfrom the base and terminating in an anvil I2 against which the jolt tablstrikes to aid in compacting the molding sand or other materials.

The base It may be of any suitable shape and has a relatively flatbottom adapted to rest upon a suitable foundation. The outer tubularshell II projects upwardly with respect to the base II] and. serves notonly as an anvil against which the jolt table 24 may strike, but also asthe protecting shield to prevent molding sand or other foreign abrasivesubstances from coming into the interior of the machine. The upper endof the anvil I2 is provided with a flat annular face I3 against whichthe jolt cable strikes.

In the basic unit illustrated in Figure 1 of the drawing, the cylinder29 is the inner portion of a central core member I4. The core I 4 has anannular wall I5 defining a stationary piston mounted upon the base I 0,and the jolt table has a central flange which constitutes a cylinder I6adapted to cooperate with the piston I5.

The core I4 is closed across the top by wall I1, and the wall I'I,coacting with the area of the table 24 within the cylinder wall I6,defines an extensible chamber I9 adapted to receive fluid underpressure. Thus, fluid may be entered into the chamber I9 through aconvenient line 20 and the table 24 may be raised with respect to thecore I4. Chamber I9 is employed in the illustrated embodiment of theinvention as a squeeze chamber to push the table 24 steadily upward witha constant force. This action is employed trated in Figure 1, thecylinder 29 is a part of the core I4, and is stationary with respect tothe base ID. The piston I8 is adapted to reciprocate vertically withinthe cylinder 29. A piston rod 22 extends through an opening 23 in thetop wall I1, and is secured by any suitable means, such, for example, asby the nut 38, to the table 24. In the preferred embodiment, it isdesirable to provide a large opening 23 and place a packing ,3I toprevent blow-by, and a guide bushing 54 therein in order that fluidpressure may be introduced between piston I8 and wall I! for return ofthe table 24 when the unit is used in the roll-overdraw type of machineillustrated in Figure '7.

The cylinder 29 is closed at the bottom by an exhaust plate 32. Theexhaust plate 32 has an entrance port portion 4| in the form of athreaded plug, and an exhaust line 33. The plug port 4'I may bevertically adjusted with respect to the plate 32 and piston l8 becauseof the threadable engagement with plate 32, and may be locked in anyselected position by a lock nut 55. The exhaust line 33 connects with anexhaust duct 34 through the base of the core I4. The exhaust duct 34leads into a chamber 35 defined by the shell II around the core memberl4. The exhaust plate 32 and the piston I8 define an extensible joltchamber 38. Fluid under pressure is introduced into the extensiblechamber 36 through means of a connecting series of conduits 31 suitablyprovided in the well-known manner. Fluid is exhausted from theextensible chamber 36 through the exhaust line 33 and exhaust duct 34through the chamber 35 and out between the surfaces I3 and 28 on theshell II and table 24, respectively.

The plug port 4| in the embodiment illustrated in Figure 1 has avertical cylindrical opening 42. Valve rod 38 is carried by the pistonI8 and is located to enter into the cylindrical opening 42 when thetable 24' and piston I8 are in the lower position illustrated inFigure 1. The valve rod 38 is dimensioned to closely fit into thecylindrical opening 42, and thereby efiectively block off the passage ofair from the chamber 36 out through the exhaust line 33.

An intake port 39 is provided in the wall of the piston I8 and ispositioned to form a continuation of the conduit system 3'! when thepiston I 8 is in 'an exhaust port arrangement similar to the conduitsystem 31 which will be uncovered by upward movement ofthe piston l8,and therefore, after .4 a predetermined rise of the piston I8 the fluidunder pressure would be exhausted from the power cylinder and the upwardforce relieved from the piston I8. Such a construction must bedetermined at the time the machine is constructed, and thereafter noalteration short of remodeling is possible to alter the length of theupward stroke under a predetermined load.

When fluid under pressure isconducted into the chamber 36, a relativelyhigh moving pressure will be built up before the inertia of the table 24and its load is overcome. Thereafter, even though the port 39 has movedto the closed position illustrated in Figure 2 of the drawings, the

.fiuid under pressure will continue to force the piston I8 upwardly fora considerable distance. This phenomena is well understood by thoseskilled in the art. The upward movement of the piston I8 may be arrestedprior to the normal complete travel by opening of the exhaust line. Aspreviously explained, opening of the exhaust line has heretofore beenaccompanied by uncovering of an exhaust port by upward movement of thepower piston. In the illustrated device of this invention, the valve rod38 extends into the cylindrical opening 42 a predetermined distance, andtherefore will not withdraw from the opening 52 until after apredetermined rise of the piston I8. After the piston I8 has risen adistance sufficient to withdraw the rod 38 from the opening 42, thefluid under pressure will be exhausted from the chamber 36 through theexhaust line 33. Hence, this invention provides a means to control thelength of the upward stroke in accordance with the weight of the table24 and the load upon the table 24. Therefore, if the table 24 is tocarry a light load, the plug II is adjusted to telescope with rod 38only a short distance and thus open the exhaust relatively soon afterthe initial upward movement begins. For heavier loads the plug M isadjusted to extend the rod 38 far into the opening 42, and thus permitthe fluid under pressure within the chamber 36 to continue acting uponthe cylinder I8 for a longer period of time.

A further feature of this invention comprises the adjustment of thethroat size from opening 42 into line 33. Heretoforethe exhaust linefrom the power chamber was fixed by the size of the opening provided atthe time the machine was built. Thus, exhaust from the power chamber washeretofore allowed to escape at the same rate, regardless of whether thetable 24 carried a heavy load or a light load. As a consequence,whenever a heavy load was carried by the table 24, the table 24 wouldforce the piston I8 down very rapidly and the surfaces 28 and I3 wouldhit exceedingly hard and cause a violent jolt, often to the extent ofdestroying the bond of the molding sand being molded. This defect in theprior devices has been corrected in this invention by the provision ofthe adjustable throat. In the embodiment of the adjustable throatillustrated, a needle valve 44 is threadably extended through the bottomof the plug 4| toward the cylindrical opening 42. Openings 58 provide apassageway from opening 42 into line 33, and the needle 44 can beadjusted to cover any proportionate area at the openings 58. The needle44 is held in a selected position by lock nut 51. Thus, the effectivefluid carrying area of the cylindrical opening 42 may be controlled byadjustment of the needle valve 44. Therefore, the rate of exhaust may becontrolled and provide a fluid cushion to retard the downward movementof the piston I8.

Further, when the rod 38 enters into the cylindrical opening 42, theexhaust action will be discontinued immediately and a considerableamount of fluid will be trapped in the chamber 35 and be compressed bythe downward movement of the piston I8, thus building up a continuallyincreasing resistance to downward movement of the piston I8 and providea cushion to prevent extremely hard jolts.

In the Figures 3 and 5, an alternative embodiment of the improved joltmachine of this invention is illustrated, wherein the piston H8 isstationary, and the cylinder I29 is movable. with the.

table 24. In this embodiment, the valve rod I38 is adjustably carried bythe table 24, and the exhaust line I33 is provided through the centralaxis of the piston rod I22. Entrance port MI is carried by the piston II8, and therefore is stationary with respect to the movable valve rodI33. The valve rod I38 is longitudinally adjustable'by the provision ofthe threadable attachment to the table 24 as illustrated. The end of therod I33 is provided with a socket opening 45 for convenient longitudinaladjustment. Entrance of fluid under pressure is substantially the sameas described in connection with th embodiment of Figure 1, and isconducted into the chamber I36 through the conduit assembly I31 andintake port I39.

In both of the illustrated embodiments, the entrance ports M and MI areillustrated as being female types, and the valve rods as being maletypes. However, this condition may readily be altered if desired, andthe rod 38 may be provided with an opening to extend down over theoutside of a cylindrical entrance port portion.

A control assembly 40 of any suitable kind may be provided to deliverfluid under compression to the conduit assemblies 31 and I31.

Although the invention has been described in its preferred form with acertain degree of particularity, it is understood that the presentdisclosure of the preferred form has been made only by way of exampleand that numerous changes in the details of construction and thecombination and arrangement of parts may be resorted to withoutdeparting from the spirit and the scope of the invention as hereinafterclaimed.

What is claimed is:

1. In a jolt mold making machine having a jolt table operated by arelatively movable piston member and cylinder member defining anextensible fluid pressure chamber, said chamber having a fluid entranceline and a fluid exhaust line, the provision of improved cushion valvemeans on said exhaust line comprising, a port member entrance to saidexhaust line, said port member having a longitudinal entrance chambertherein, a longitudinal rod having a crosssectional configurationsimilar to the cross-sectional configuration of said entrance chamber ofthe port member, but smaller to the extent that the rod interfits intothe entrance chamber, said port member bein carried by one of therelatively movable members, longitudinal adjustment mounting meansmounting said longitudinal rod on the other relatively movable member,the relative movement of the rod and port member being along a commonlongitudinal path common to the longitudinal axis of the rod andentrance chamber, said port member being longitudinally adjustable alongsaid path with respect to the member carrying said rod to provide aselected degree of telescoping of the rod into the entrance chamber.

2. In a jolt mold making machine having a jolt table operated by arelatively movable piston member and cylinder member defining anextensible fluid pressure chamber, said chamber having a fluid entranceline and a fluid exhaust line, the provision of improved cushion valvemeans on said exhaust line comprising, a port member entrance to saidexhaust line, said port member having a longitudinal entrance chambertherein, a longitudinal rod having a crosssectional configurationsimilar to the cross-sectional configuration of said entrance chamber ofthe port member, but smaller to the extent that the rod interfits intothe entrance chamber, said port member being carried by one of threlatively movable members, longitudinal adjustment mountin meansmounting said longitudinal rod on the other relatively movable member,the relative movement of the rod and port member being along a commonlongitudinal path common to the longitudinal axis of the rod andentrance chamber, said port member being longitudinally adjustable alongsaid path with respect to the member carrying said rod to provide aselected degree of telescoping of the rod into the entrance chamber,said exhaust line having a maximum fluid carrying capacity, linereducing valve means in said exhaust line, and valve operating controlmeans extendin from said valve means to a position accessible externallyof the jolt machine while that machine is in operation, whereby a givenload may be placed upon the table and the exhaust outlet regulated whilethe jolt machine is in operation to give a precision degree of jolt.

3. In a jolt mold making machine having a jolt table operated by arelatively movable piston member and cylinder member defining anextensible fluid pressure chamber, said chamber having a fluid entranceline and a fluid exhaust line, the provision of improved cushion valvemeans on said exhaust line comprising, a port member entrance to saidexhaust line, said port member having a longitudinal entrance chambertherein, a longitudinal rod having a crosssectional configurationsimilar to the cross-sectional configuration of said entrance chamber ofthe port member, but smaller to the extent that the rod interfits intothe entrance chamber, said port member being carriedby one of therelatively movable members, means mounting said longitudinal rod on theother relatively movable member, the relative movement of the rod andport member being along a common longitudinal path common to thelongitudinal axis of the rod and entrance chamber, and means to adjustsaid rod and said port member longitudinally along said path withrespect to one another and thereby provide a selected degree oftelescoping of the rod into the entrance chamber.

LESTER C. YOUNG.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 1,157,403 Lewis Oct. 19, 19151,274,752 Norcross Aug. 6, 1918 1,547,056 MacNeill July 21, 19251,642,074 Lewis sept. 13, 1927 1,932,803 Radigan Oct. 31, 1933 2,438,218Johnston Mar. 23, 1948 FOREIGN PATENTS Number Country Date 547,749Germany Mar. 29, 1932

